scholarly journals EFFECTS OF VISCOELASTIC PROPERTIES AND HYDRATION KINETIC ON DRUG RELEASE FROM THE TABLET OF DICLOFENAC SODIUM BASED ON POLY (SODIUM ACRYLATE)-GRAFTED-GELLAN MATRIX

2019 ◽  
Vol 9 (4-A) ◽  
pp. 1-8
Author(s):  
Gouranga Nandi
Keyword(s):  
Drug Release ◽  
Phosphate Buffer ◽  
Diclofenac Sodium ◽  
Phosphate Buffer Solution ◽  
Fickian Diffusion ◽  
Sodium Acrylate ◽  
Release Mechanism ◽  
Drug Release Profile ◽  
Buffer Solution ◽  
Solution Ph

Investigation of the effects of viscoelasticity and hydration kinetic on the drug release behavior from the poly (sodium acrylate)-grafted-gellan matrix (PSAc-g-GG) was the main objective of this study. At first, poly (acrylic acid)-grafted-gellan was treated with 0.05M NaOH to obtain poly (sodium acrylate)-grafted-gellan followed by its purification and subsequent lyophilicity study and viscoelastic study on PSAc-g-GG with different degree of grafting. The study revealed that the degree of grafting greatly affects the viscoelastic and rheologic characteristics of the copolymer, which further affect the drug release profile from the polymeric matrix. The  copolymer with highest grafting (626.3%) exhibited much higher starting % strain (17.79%), stress (53.7 Pa) for structural breakdown at Gꞌ = Gꞌꞌ (214.4 Pa), higher storage modulus (G’), much greater values of complex viscosity (11.5 Pa.s) and cross-over point (Gꞌ = Gꞌꞌ =271.65 Pa) compared to that of the batch of copolymer with lower grafting. The water uptake index (%WE) was found to be directly proportional to the percentage grafting (%G), whereas the batches with higher grafting  revealed lower initial swelling rate representing its inversely proportional relation to %grafting in case of 0.1N HCl acid. Equilibrium swelling and hydration were also found to be proportional to % grafting.  The similar effect was observed in phosphate buffer solution (pH 6.8) with an exception that the degree of the swelling parameters obtained from phosphate buffer was very much greater compared to that found in 0.1N HCl. PSAc-g-GG exhibited extended drug release over a period of 10 hours with the drug release mechanism based on Case-1 Fickian diffusion or square root of time kinetic. The study also exhibited the usefulness of viscoelastic and swelling study in order to identify the effects of the degree of grafting on the drug release.

scholarly journals Carbon-Based Magnetic Nanocarrier for Controlled Drug Release: A Green Synthesis Approach

2018 ◽  
Vol 5 (1) ◽  
pp. 1 ◽  
Author(s):  
Jessica Oliveira ◽  
Raquel Rodrigues ◽  
Lillian Barros ◽  
Isabel Ferreira ◽  
Luís Marchesi ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Magnetic Nanoparticles ◽  
Drug Release ◽  
Phosphate Buffer ◽  
Colloidal Stability ◽  
Ph Dependence ◽  
Phosphate Buffer Solution ◽  
Controlled Drug Release ◽  
Buffer Solution ◽  
Carbon Based

In this study, hydrophilic magnetic nanoparticles were synthesized by green routes using a methanolic extract of Rubus ulmifolius Schott flowers. The prepared magnetic nanoparticles were coated with carbon-based shell for drug delivery application. The nanocomposites were further chemically functionalized with nitric acid and, sequentially, with Pluronic® F68 (CMNPs-plur) to enhance their colloidal stability. The resulting material was dispersed in phosphate buffer solution at pH 7.4 to study the Doxorubicin loading. After shaking for 48 h, 99.13% of the drug was loaded by the nanocomposites. Subsequently, the drug release was studied in different working phosphate buffer solutions (i.e., PB pH 4.5, pH 6.0 and pH 7.4) to determine the efficiency of the synthesized material for drug delivery as pH-dependent drug nanocarrier. The results have shown a drug release quantity 18% higher in mimicking tumor environment than in the physiological one. Therefore, this study demonstrates the ability of CMNPs-plur to release a drug with pH dependence, which could be used in the future for the treatment of cancer "in situ" by means of controlled drug release.

Synthesis, characterization, and drug delivery property of 2-N-carboxymethyl-6-O-diethylaminoethyl-chitosan

e-Polymers ◽  
2013 ◽  
Vol 13 (1) ◽  
Author(s):  
Aidi Zhang ◽  
Derun Ding ◽  
Jicun Ren ◽  
Xiangli Zhu ◽  
Youhong Yao
Keyword(s):  
Phosphate Buffer ◽  
Phosphate Buffer Solution ◽  
Controlled Delivery ◽  
Protective Agent ◽  
Buffer Solution ◽  
Solution Ph ◽  
H Nmr ◽  
Structure Morphology ◽  
Ft Ir ◽  
Model Drug

Abstract A novel route is demonstrated for the synthesis of 2-N-carboxymethyl-6- O-diethylaminoethyl-chitosan (DEAE-CMC) by incorporation of carboxymethyl groups as hydrophilic moieties to the C2-NH2, and diethylaminoethyl groups as hydrophobic moieties to the C6-CH2OH of the structural unit of chitosan, via a protection-graft-deprotection procedure with benzaldehyde as protective agent. The structure, morphology, and thermal properties of the chitosan graft copolymers were characterized by means of FT-IR, 1H NMR, SEM, TGA and DSC. Chitosan and its derivatives were used as carrier of model drug-Vitamin B12 (VB12), and their controlled delivery behaviour in phosphate buffer solution (pH 7.4) were studied. The results show that the release rate of VB12 from the carrier of DEAE-CMC copolymer becomes much slower than that of chitosan in phosphate buffer solution.

Glucose electro-oxidation on Pt(100) in phosphate buffer solution (pH 7): A mechanistic study

2020 ◽  
Vol 354 ◽  
pp. 136765 ◽  
Author(s):  
Gisele A.B. Mello ◽  
William Cheuquepán ◽  
Valentín Briega-Martos ◽  
Juan M. Feliu
Keyword(s):  
Phosphate Buffer ◽  
Phosphate Buffer Solution ◽  
Mechanistic Study ◽  
Buffer Solution ◽  
Solution Ph ◽  
Electro Oxidation

scholarly journals Fast Drug Release Using Rotational Motion of Magnetic Gel Beads

2008 ◽  
Vol 2008 ◽  
pp. 1-5 ◽  
Author(s):  
Tetsu Mitsumata ◽  
Yusuke Kakiuchi ◽  
Jun-Ichi Takimoto
Keyword(s):  
Drug Release ◽  
Magnetic Fields ◽  
Rotational Motion ◽  
Phosphate Buffer Solution ◽  
Fickian Diffusion ◽  
Buffer Solution ◽  
Time Profiles ◽  
Gel Beads ◽  
High Elasticity ◽  
Fast Release

Accelerated drug release has been achieved by means of the fast rotation of magnetic gel beads. The magnetic gel bead consists of sodium alginate crosslinked by calcium chlorides, which contains barium ferrite of ferrimagnetic particles, and ketoprofen as a drug. The bead underwent rotational motion in response to rotational magnetic fields. In the case of bead without rotation, the amount of drug release into a phosphate buffer solution obeyed non-Fickian diffusion. The spontaneous drug release reached a saturation value of 0.90 mg at 25 minutes, which corresponds to 92% of the perfect release. The drug release was accelerated with increasing the rotation speed. The shortest time achieving the perfect release was approximately 3 minutes, which corresponds to 1/8 of the case without rotation. Simultaneous with the fast release, the bead collapsed probably due to the strong water flow surrounding the bead. The beads with high elasticity were hard to collapse and the fast release was not observed. Hence, the fast release of ketoprofen is triggered by the collapse of beads. Photographs of the collapse of beads, time profiles of the drug release, and a pulsatile release modulated by magnetic fields were presented.

Preparation and Characterization of Danazol Nanoparticles for Dissolution Improvement

2018 ◽  
Vol 9 (SPL1) ◽  
Author(s):  
Luma Safa el-din Al-Hassnaui
Keyword(s):  
Particle Size ◽  
Phosphate Buffer ◽  
Phosphate Buffer Solution ◽  
Amorphous State ◽  
Volume Ratio ◽  
In Vitro Dissolution ◽  
Buffer Solution ◽  
Solution Ph ◽  
Freeze Dried

Danazol is a synthetic steroid used for endometriosis treatment, haslow bioavailability as it is practically insoluble in water. This study has been carried out to prepare and characterize danazol nanoparticles by nanoprecipitation method at a different polymer to drug ratios of 0.5:1,1:1,2:1 and 3:1 using different polymers of CMC-30 and various grades of HPMC and PVP,as stabilizers. Variables that might affect the particle size as polymer type,polymer to drug ratio,temperature of precipitation,addition rate of danazol solution,volume ratio,time of stirring,concentrationof drug,have been investigated. The particle size of the prepared formulas has been in the nano-sized except those using CMC and the best formula has beenF20 at a polymer to drug ratio of0.5:1 which has given the smallest particle sizeof 33nm.The investigations of the drug–stabilizer compatibility havebeen studied by FTIR and DSC,crystalline state by XRD,size,and shape of nanoparticles by FESEM and the results showed that there has been no interaction between the danazol and stabilizer and there has been a partial conversion of danazol from crystalline to an amorphous state with a size below 100nm. Most of the studied factors havebeen found affect the particle size of the nanoparticles.The Entrapment efficiency has been (91.3% ± 0.4) in the (F20). The solubility study revealed that 6.75,4.97 and 5.1 folds increased of solubility of danazol for nanoparticles than that for raw in distilled water,0.1N HCl and in phosphate buffer of pH 6.8.The simple capsule has been prepared by incorporation of freeze-dried of F20 with lactose as a filler and the in vitro dissolution study has been conducted using 0.1N HCl (pH 1.2) with 2% w/v Brij-35,phosphate buffer solution(pH 6.8) with 2% w/v Brij-35as dissolution media. Within 30 minutes,100% of the danazol has been released from the nanoparticle capsule in both dissolution media compared to the raw and physical blend capsules as controls havebeen nearly complete in 120 minutes.One can conclude that Antisolvent method is an easy,efficient method to prepare danazol nanoparticles with an intense effect on solubility and faster in vitro dissolution rate than raw drug and its physical blend with stabilizer.

Synthesis of antimicrobial polymer composition and in vitro drugs release study

e-Polymers ◽  
2008 ◽  
Vol 8 (1) ◽  
Author(s):  
Tudorachi Nita
Keyword(s):  
Diclofenac Sodium ◽  
Phosphate Buffer Solution ◽  
Polymer Composition ◽  
Size Analysis ◽  
Colloidal Silver ◽  
Silver Particles ◽  
Buffer Solution ◽  
Solution Ph ◽  
Oh Groups

AbstractThe study presents a procedure to acquire a colloidal silver-based antimicrobial polymer composition. Carboxymethylstarch (CMS) as polymer matrix, and colloidal silver particles (Ag0) obtained by in situ synthesis with silver nitrate and sodium citrate as reducing agent, were used. In solution, the presence of COOH and OH groups in carboxymethylstarch directs to silver complexation and acquirement of a stable suspension of silver particles. Due to the presence of colloidal silver particles, the composition presents bacteriostatic activity and in association with some drugs (acetylsalicylic acid or diclofenac sodium) pharmaceutical compositions can be obtained, which are useful in the prevention and treatment of some infections or diseases. The compositions were characterized by FTIR spectroscopy, UV-vis spectrophotometry, particle size analysis and zeta potential measurements. Drug release tests were done in vitro in phosphate buffer solution (pH=7.4, at 37°C).

Grewia asiatica Mucilage: A Smart Gelling Polymeric Material for Pharmaceutical Applications In Vitro Studies

2020 ◽  
Vol 12 (2) ◽  
pp. 117-126
Author(s):  
Nitin Gupta ◽  
Giriraj T. Kulkarni ◽  
Pravin Kumar ◽  
Rajendra Awasthi
Keyword(s):  
Drug Release ◽  
Polymeric Material ◽  
Diclofenac Sodium ◽  
Skin Irritation ◽  
In Vitro Release ◽  
Penetration Enhancers ◽  
Release Mechanism ◽  
Drug Release Profile ◽  
Therapeutic Benefits

Background: Natural plant-based materials have several advantages. They are biodegradable, biocompatible, non-toxic, cost-effective, environment friendly, easily available, and can undergo chemical modification. Objective: Grewia asiatica extracts contain various phytoconstituents and have therapeutic benefits such as antimicrobial and anti-diabetic properties. They form colloidal dispersions and make a highly viscous gel in water. Considering these properties of Grewia asiatica mucilage, the present work was aimed to investigate its application in the formulation of gel for the topical delivery of diclofenac sodium. Method: Gel formulations were prepared with and without penetration enhancers using 1% w/w diclofenac sodium as a model drug. The formulations were subjected to different evaluation tests like physical characterization, pH, spreadability, skin irritation, gel retrogradation, drug content and in vitro drug diffusion. The in vitro diffusion of the drug from different formulations was compared with the in vitro drug release profile of the marketed formulation (Omni gel, Cipla, India). To assess the release mechanism, the in vitro release data was analyzed using Korsmeyers-Peppas’ equation. Results: The mucilage showed good gelling behavior in 5.50, 5.75, 6.00, 6.25 and 6.50% concentrations. All the formulations followed the anomalous transport mechanism of drug release. The formulation BP3 showed 90% of drug release after 5.2h of dissolution study, which was similar to the marketed formulation. Hence, formulation BP3 was ideal among all the formulations. Conclusion: It might be concluded that, the Grewia asiatica mucilage may be used as a natural polymeric material for gel formulation.

scholarly journals Spectrophotometric Determination of Lorsartan Potassium and its Dosage Form by Bromothymol Blue and Phosphate Buffer

2010 ◽  
Vol 7 (1) ◽  
pp. 320-324 ◽  
Author(s):  
L. Latheeshjlal ◽  
P. Parthiban ◽  
V. Alagarsamy ◽  
M. Sunil ◽  
J. Vaidhya Mahul ◽  
...  
Keyword(s):  
Spectrophotometric Method ◽  
Phosphate Buffer ◽  
Dosage Form ◽  
Phosphate Buffer Solution ◽  
Accurate Method ◽  
Bromothymol Blue ◽  
Losartan Potassium ◽  
Buffer Solution ◽  
Solution Ph

Simple, rapid and accurate, spectrophotometric method for the determination of losartan potassium by using bromothymol blue as a chromogen and phosphate buffer solution (pH 3-4) as a diluting agent was developed. The developed colour shows maximum absorbance at 620 nm and it was observed that the absorbance of different dilution from the plots the calibration curve between the concentrations in x-axis, absorbance at y-axis. The recovery studies were also carried out to ensure the reproducibility and repeatability. This recovery studies shows between 96.82-100.08% for the different formulation. Hence, it was concluded that the developed simple, precise and accurate method can be effectively used for the routine analysis of losartan potassium

scholarly journals Morphological characteristics of Candida albicans, Candida krusei, Candida guilliermondii, and Candida glabrata biofilms, and response to farnesol

2021 ◽  
pp. 1608-1614
Author(s):  
Nadezhda Sachivkina ◽  
Irina Podoprigora ◽  
Dmitry Bokov
Keyword(s):  
Candida Albicans ◽  
Phosphate Buffer ◽  
Candida Species ◽  
Candida Glabrata ◽  
Phosphate Buffer Solution ◽  
Morphological Characteristics ◽  
Candida Guilliermondii ◽  
Candida Krusei ◽  
Buffer Solution ◽  
Solution Ph

Background and Aim: Different Candida species isolated in humans and animals have different types of parasite activity. The most pathogenic species is Candida albicans followed by Candida tropicalis. However, the effects of the morphology of Candida krusei, Candida guilliermondii, and Candida glabrata biofilms on the pathogenicity of these species have not been fully characterized. To the best of our knowledge, there is no literature on the effect of farnesol on rare Candida species. This study aimed to check the effect of different farnesol concentrations on the species C. krusei, C. guilliermondii, and C. glabrata compared with the strain C. albicans ATCC 10231, which has been widely studied, and is a strong producer of biofilms. Materials and Methods: We studied the morphological and densitometric parameters of biofilms produced by Candida species under the influence of the drug farnesol (Sigma-Aldrich, St. Louis, MO). We used a heart brain broth with the addition of 2% bovine blood serum in 96-well plates. To each well, we added 100 μL of C. albicans, C. krusei, C. guilliermondii, or C. glabrata culture, and 0.2-400 μM farnesol. The microliter plates were cultured with the lid closed at 37°C for 48 h. Then, the liquid was removed, and the wells were washed 3 times with 200 μL phosphate buffer solution (pH 7.3). Biofilm fixation was performed using 150 μL of 96% ethanol for 15 min. Then, the microliter plates were dried for 20 min at 37°C, a 0.5% solution of crystalline violet was added, and the plates were placed in an incubator at 37°C. After 5 min, the contents of the wells were removed, washed 3 times with 200 μL of phosphate buffer solution (pH 7.2), and dried. The dye was extracted by washing with 200 μL of 96% ethanol for 30 min. The results were obtained using a photometric analyzer of enzyme immunoassay reactions at an optical density (OD) wavelength of 450 nm. Results: All of Candida spp. strains tested were susceptible to farnesol at concentrations ranging from 0.8 to 400 μM for C. albicans, C. krusei, and C. guilliermondii, and 12.5 to 400 μM for C. glabrata. Conclusion: This study provides new insights into the use of farnesol against biofilms produced by Candida species, but further studies in vivo are necessary to evaluate the effectiveness of the reduction of OD. To the best of our knowledge, the antimicrobial activity of farnesol against C. krusei, C. guilliermondii, and C. glabrata has not been reported previously, although studies have confirmed the inhibitory effect of farnesol on the growth of different microorganisms.

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